Which of the following tables represents a linear function?
x 1 1 1 1 1
y −3 −2 −1 0 1
x −4 −2 0 2 4
y 4 2 0 2 4
x −5 −3 −1 1 3
y negative one half 1 2 7 over 2 5
x −6 −4 −2 0 2
y 5 13 over 3 11 over 3 3 7 over 3
Solution
To determine which table represents a linear function, we need to check if the change in y is consistent for equal changes in x. A function y=mx+b is linear if the differences between consecutive y values divided by the differences between the corresponding x values (i.e., the slope) are constant.
Let's analyze each table:
Table 1
x 1 1 1 1 1 y −3 −2 −1 0 1
The x values are all the same, so we cannot determine a slope. This is not a function.
Table 2
x −4 −2 0 2 4 y 4 2 0 2 4
Calculate the slope between each pair of points:
Slope between (−4,4) and (−2,2)=−2−(−4)2−4=2−2=−1Slope between (−2,2) and (0,0)=0−(−2)0−2=2−2=−1Slope between (0,0) and (2,2)=2−02−0=22=1Slope between (2,2) and (4,4)=4−24−2=22=1
The slopes are not consistent, so this is not a linear function.
Table 3
x −5 −3 −1 1 3 y −1/2 1 2 7/2 5
Calculate the slope between each pair of points:
Slope between (−5,−21) and (−3,1)=−3−(−5)1−(−21)=21+21=223=43Slope between (−3,1) and (−1,2)=−1−(−3)2−1=21=21Slope between (−1,2) and (1,27)=1−(−1)27−2=227−24=223=43Slope between (1,27) and (3,5)=3−15−27=2210−27=223=43
The slopes are consistent, so this is a linear function with slope 43.
Table 4
x −6 −4 −2 0 2 y 5 313311 3 37
Calculate the slope between each pair of points:
Slope between (−6,5) and (−4,313)=−4−(−6)313−5=2313−315=23−2=3−1Slope between (−4,313) and (−2,311)=−2−(−4)311−313=23−2=3−1Slope between (−2,311) and (0,3)=0−(−2)3−311=239−311=23−2=3−1Slope between (0,3) and (2,37)=2−037−3=237−39=23−2=3−1
The slopes are consistent, so this is a linear function with slope 3−1.
Conclusion
The tables that represent a linear function are Table 3 and Table 4.
Would you like more details or have any questions?
Here are some questions you can ask next:
How do you find the slope of a line given two points?
Can you explain the properties of linear functions?
What is the difference between a linear and a nonlinear function?
How do you graph a linear equation?
What is the significance of the y-intercept in a linear function?
Tip: To determine if a set of points forms a linear function, always check if the change in y is proportional to the change in x for all pairs of points.